diff options
author | Paul Mackerras | 2018-09-21 20:02:01 +1000 |
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committer | Paul Mackerras | 2018-10-09 16:14:47 +1100 |
commit | aa069a996951f3e2e38437ef0316685a5893fc7e (patch) | |
tree | 40de54d39eeb75cb318b221a3d497a032ca72ab4 /Documentation/virtual/kvm | |
parent | 9d67121a4fce20e0f7f127d40cd824fbbf5297dc (diff) |
KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization
With this, userspace can enable a KVM-HV guest to run nested guests
under it.
The administrator can control whether any nested guests can be run;
setting the "nested" module parameter to false prevents any guests
becoming nested hypervisors (that is, any attempt to enable the nested
capability on a guest will fail). Guests which are already nested
hypervisors will continue to be so.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'Documentation/virtual/kvm')
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 2f5f9b743bff..fde48b6708f1 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -4532,6 +4532,20 @@ With this capability, a guest may read the MSR_PLATFORM_INFO MSR. Otherwise, a #GP would be raised when the guest tries to access. Currently, this capability does not enable write permissions of this MSR for the guest. +7.16 KVM_CAP_PPC_NESTED_HV + +Architectures: ppc +Parameters: none +Returns: 0 on success, -EINVAL when the implementation doesn't support + nested-HV virtualization. + +HV-KVM on POWER9 and later systems allows for "nested-HV" +virtualization, which provides a way for a guest VM to run guests that +can run using the CPU's supervisor mode (privileged non-hypervisor +state). Enabling this capability on a VM depends on the CPU having +the necessary functionality and on the facility being enabled with a +kvm-hv module parameter. + 8. Other capabilities. ---------------------- |